Microwave white chocolate in small microwave-safe bowl on high for 45 seconds. Stir. Microwave 30 seconds; stir until smooth. Transfer to small pastry bag fitted with medium writing tip, or small heavy-duty plastic bag; snip off corner. Pipe in parallel lines, 1/2 inch apart, across chocolate. Run tip of knife across white stripes, alternating directions with each pass, to form feathered pattern. Refrigerate until firm, 30 minutes. Cut into bars. Makes 30 bars.